Question

LCM of (x-y) and 2(y-x)

Answer 1

If you change the x and y to real numbers such as -2 and 3 the x-y=-5 and y-x=3--2=5 then multiply by 2 to get 10.
So, I would thin that the LCM might be
-2. Try it out in a few more weird number situations and see if it works.